Valve system

ABSTRACT

A valve comprising a base plate defining an inlet and outlet passageway. A cover plate is disposed on the base plate and defines a first and second channel. A pressure plate is disposed on the base plate and includes a first anchoring portion, a first sealing portion, and a first biasing portion connecting the first anchoring portion and the first sealing portion. Furthermore, a suction plate is disposed on the base plate and includes a second anchoring portion, a second sealing portion, and a second biasing portion connecting the second anchoring portion to the second sealing portion. The valve is movable between a first configuration, where the first sealing portion is distal to first channel and the second sealing portion is proximal to inlet passageway, and a second configuration, in which the first sealing portion is proximal to first channel, and second sealing portion is distal to inlet passageway.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a divisional of U.S. patent application Ser.No. 14/658,762 filed Mar. 16, 2015, the contents of which areincorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates generally to valves and pumps for pumpingfluid.

BACKGROUND

Exhaust aftertreatment systems are used to receive and treat exhaust gasgenerated by internal combustion (IC) engines. Conventional exhaust gasaftertreatment systems include any of several different components toreduce the levels of harmful exhaust emissions present in exhaust gas.For example, certain exhaust aftertreatment systems for diesel-poweredIC engines include a selective catalytic reduction (SCR) catalyst toconvert NOx (NO and the NO₂ in some fraction) into harmless nitrogen gas(N₂) and water vapor (H₂O) in the presence of ammonia (NH₃).

The ammonia used by the SCR system for reducing the exhaust gas isgenerally provided in the form of a liquid exhaust reductant. The liquidexhaust reductant is stored in an exhaust reductant tank andcommunicated into the SCR system from the tank via a pump. Pumps usedaftertreatment should preferable have a small form factor, be robust andbe able to resist corrosion from the exhaust reductant.

SUMMARY

In various embodiments, a valve comprises a base plate defining an inletpassageway and an outlet passageway. The inlet passageway is included ina suction portion of the valve, and the outlet passageway is included ina pressure portion of the valve. A cover plate is disposed on the baseplate. The cover plate defines a first channel in the pressure portionand a second channel in the suction portion. A pressure plate isdisposed on the base plate in the pressure portion. The pressure plateincludes a first anchoring portion, a first sealing portion, and a firstbiasing portion connecting the first anchoring portion and the firstsealing portion. Furthermore, a suction plate is disposed on the baseplate in the suction portion. The suction plate includes a secondanchoring portion, a second sealing portion, and a second biasingportion connecting the second anchoring portion to the second sealingportion.

The valve is movable between a first configuration and a secondconfiguration. In the first configuration, the first sealing portion ofthe pressure plate is distal to the first channel and the second sealingportion of the suction plate is proximal to the inlet passageway. In thesecond configuration the first sealing portion of the pressure plate isproximal to the first channel, and the second sealing portion of thesuction plate is distal to the inlet passageway. In particularembodiments, the movement of the first sealing portion and the secondsealing portion between the first configuration and the secondconfiguration results in a flexing of the first biasing portion aboutthe first anchoring portion, and a flexing of the second biasing portionabout the second anchoring portion, respectively.

In other embodiments, a pump comprises a valve. The valve comprises abase plate defining an inlet passageway and an outlet passageway. Theinlet passageway is included in a suction portion of the valve, and theoutlet passageway is included in a pressure portion of the valve. Acover plate is disposed over the base plate. The cover plate defines afirst channel in the pressure portion and a second channel in thesuction portion. A pressure plate is disposed on the base plate in thepressure portion. The pressure plate includes a first anchoring portion,a first sealing portion, and a first biasing portion connecting thefirst anchoring portion and the first sealing portion. A suction plateis disposed on the base plate in the suction portion. The suction plateincludes a second anchoring portion, a second sealing portion, and asecond biasing portion connecting the second anchoring portion and thesecond sealing portion. A membrane is disposed on the cover plate suchthat the membrane and the cover plate define a chamber therebetween. Thepressure portion and the suction portion are in fluidic communicationthrough the first channel and the second channel via the chamber.

The pump is movable between a first configuration and a secondconfiguration. In the first configuration, the membrane is proximal tothe cover plate. The first sealing portion of the pressure plate isdistal to the first channel such that a fluid is expelled from thechamber into the outlet passageway through the first channel.Furthermore, the second sealing portion of the suction plate is proximalto the inlet passageway and fluidly seals the inlet passageway. In thesecond configuration, the membrane is distal to the cover plate. Thefirst sealing portion is proximal to the first channel and fluidly sealsthe first channel. The second sealing portion is distal to the inletpassageway such that the fluid is drawn into the chamber from the inletpassageway via the second channel.

In still other embodiments, an aftertreatment system comprises aselective catalytic reduction system configured to receive an exhaustgas from an engine. The selective catalytic reduction system includes atleast one catalyst formulated to reduce the exhaust gas. A storage tankis configured to store an exhaust reductant for providing to theselective catalytic reduction system. A pump is fluidly coupled to thestorage tank and the selective catalytic reduction system. The pump isconfigured to pump the exhaust reductant from the storage tank to theselective catalytic reduction system.

The pump comprises a valve comprising a base plate defining an inletpassageway and an outlet passageway. The inlet passageway is included ina suction portion of the valve, and the outlet passageway is included ina pressure portion of the valve. A cover plate is disposed over the baseplate. The cover plate defines a first channel in the pressure portionand a second channel in the suction portion. A pressure plate isdisposed on the base plate in the pressure portion. The pressure plateincludes a first anchoring portion, a first sealing portion, and a firstbiasing portion connecting the first anchoring portion and the firstsealing portion. A suction plate is disposed on the base plate in thesuction portion. The suction plate includes a second anchoring portion,a second sealing portion, and a second biasing portion connecting thesecond anchoring portion and the second sealing portion. A membrane isdisposed on the cover plate such that the membrane and the cover platedefine a chamber therebetween. The pressure portion and the suctionportion are in fluidic communication through the first channel and thesecond channel via the chamber.

The pump is movable between a first configuration and a secondconfiguration. In the first configuration, the membrane is proximal tothe cover plate. The first sealing portion of the pressure plate isdistal to the first channel such that a fluid is expelled from thechamber into the outlet passageway through the first channel. The secondsealing portion of the suction plate is proximal to the inlet passagewayand fluidly seals the inlet passageway. In the second configuration inwhich the membrane is distal to the cover plate, the first sealingportion is proximal to the first channel and fluidly seals the firstchannel. The second sealing portion is distal to the inlet passagewaysuch that the fluid is drawn into the chamber from the inlet passagewayvia the second channel.

It should be appreciated that all combinations of the foregoing conceptsand additional concepts discussed in greater detail below (provided suchconcepts are not mutually inconsistent) are contemplated as being partof the inventive subject matter disclosed herein. In particular, allcombinations of claimed subject matter appearing at the end of thisdisclosure are contemplated as being part of the inventive subjectmatter disclosed herein.

BRIEF DESCRIPTION OF DRAWINGS

The foregoing and other features of the present disclosure will becomemore fully apparent from the following description and appended claims,taken in conjunction with the accompanying drawings. Understanding thatthese drawings depict only several implementations in accordance withthe disclosure and are therefore, not to be considered limiting of itsscope, the disclosure will be described with additional specificity anddetail through use of the accompanying drawings.

FIG. 1 is a perspective view of a valve that includes a base plate, acover plate, a pressure plate and a suction plate, according to anembodiment.

FIG. 2A is a side cross-section view of the pressure portion of thevalve of FIG. 1, and FIG. 2B is a side cross-section view of the suctionportion of the valve of FIG. 1.

FIG. 3 is a side cross-section view of the valve of FIG. 1, showing thepressure plate and the suction plate in a first configuration and asecond configuration.

FIG. 4 is a perspective view of another embodiment of a valve thatincludes a base plate, a cover plate, a pressure plate and a suctionplate.

FIG. 5A is a side cross-section of a pressure portion of the valve ofFIG. 4, and FIG. 5B is a side cross-section of the suction portion ofthe valve of FIG. 4.

FIG. 6 is schematic block diagram of an aftertreatment system thatcomprises a pump which includes the valve of FIG. 1, according toanother embodiment.

FIG. 7A is a bottom view of a cover plate, and FIG. 7B is a top view ofa base plate of a valve.

FIG. 8A is a plot of pumping profile of the valve of FIGS. 7A and 7Bduring operation at a nominal system pressure, and FIG. 8B is a plotshowing suction developed in a pump that includes the valve,demonstrating the self-priming ability which can be achieved with thevalve of FIGS. 7A and 7B.

Reference is made to the accompanying drawings throughout the followingdetailed description. In the drawings, similar symbols typicallyidentify similar components, unless context dictates otherwise. Theillustrative implementations described in the detailed description,drawings, and claims are not meant to be limiting. Other implementationsmay be utilized, and other changes may be made, without departing fromthe spirit or scope of the subject matter presented here. It will bereadily understood that the aspects of the present disclosure, asgenerally described herein, and illustrated in the figures, can bearranged, substituted, combined, and designed in a wide variety ofdifferent configurations, all of which are explicitly contemplated andmade part of this disclosure.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

Embodiments described herein relate generally to a valve which can beincluded in a pump, and in particular to a metal plate valve thatincludes a first metal plate and second metal plate, which can be movedvia suction and pressure in the same direction relative to each other topump a fluid.

Various embodiments of the metal plate valve described herein mayprovide several benefits including, for example (1) providing a smallpackage which occupies a relatively small space when included in asystem, for example in an aftertreatment system; (2) providingcompatibility with existing membrane pumps allowing the valve to beincluded in conventional pumps; and (3) reducing cost and extending thelife of the valve by using a pre-tensioned metal plates for pumpingminimizing moving parts.

FIG. 1 shows a perspective view of a valve 100 which can be included ina pump, for example a pump configured to deliver an exhaust reductant toan SCR system. The valve 100 includes a base plate 102, a cover plate104, a pressure portion 110 that includes a pressure plate 112, and asuction portion 130 that includes a suction plate 132. FIG. 2A shows aside cross-sectional view of the pressure portion 110, and FIG. 2B showsa side cross-section of the suction portion 130 of the valve 100.

The base plate 102 defines an inlet passageway 136 and an outletpassageway 116 therethrough (FIGS. 2A and 2B). The inlet passageway 136is defined in the suction portion 130, and the outlet passageway 116 isdefined in the pressure portion 110 of the valve 100. The inletpassageway 136 is configured to receive a fluid (e.g., an exhaustreductant) from a fluid source (e.g., an exhaust reductant tank), andthe outlet passageway 116 is configured to expel the fluid from thevalve 100 (e.g., to communicate an exhaust reductant to an SCR system).

The base plate 102 can be a machined, molded or casted part and can beformed from any suitable strong, rigid and corrosion resistant materialsuch as metals (iron, aluminum, steel, alloys, etc.), polymers,plastics, any other suitable material or combinations thereof. The baseplate 102 can have any suitable shape, for example round, square,rectangular, oval, etc. A first cavity 111 is also defined in the baseplate 102 in the pressure portion. The first cavity 111 is configured toreceive at least a portion of the pressure plate 112, as describedherein, and is in fluidic communication with the outlet passageway 116.

The cover plate 104 is disposed on the base plate 102. The cover plate104 can be removably coupled to the base plate 102, for example viafasteners such as screws, nuts, bolts, snap-fit mechanism, any othersuitable mechanism or combinations thereof. The cover plate 104 can havea shape and which can be substantially similar to the shape of the baseplate 102, as described herein. The cover plate 104 can also be formedfrom a strong, rigid and corrosion resistant material such as metals(iron, aluminum, steel, alloys, etc.), polymers, plastics any othersuitable material or combinations thereof.

The cover plate 104 defines a first channel 122 in the pressure portion110 and a second channel 137 in the suction portion 130. The secondchannel 137 is aligned with the inlet passageway 136 when the coverplate 104 is coupled to the base plate 102. The second channel 137 isconfigured to allow the fluid communicated into the base plate 102 viathe inlet passageway 136 to be drawn out of the cover plate 104 into achamber defined between a membrane 109 (FIGS. 2A-2B and FIG. 3) whichcan be included in a pump (not shown) and a top surface of the coverplate 104. In some embodiments, at least a portion of the cover platebetween the first channel 122 and the second channel 137 can define adepression 108. The depression 108 can be structured to cooperate withthe membrane 109 disposed on the cover plate 104 to form the chamberbetween the top surface of the cover plate 104 and the membrane 109. Thechamber is configured to allow fluidic communication between the firstchannel 122 and the second channel 137. Thus, the chamber provides afluidic path for the fluid to flow from suction portion 130 to thepressure portion 110.

The first channel 122 is aligned with the outlet passageway 116 and isconfigured to allow fluid drawn into the chamber to be communicated backinto the cover plate 104 and into the outlet passageway 116. In thismanner, the fluid can be pumped through the valve 100, as described infurther detail herein.

The cover plate 104 also defines a second cavity 131 in the suctionportion 130. The second cavity 131 is configured to receive at least aportion of the suction plate 132, as described herein and is in fluidiccommunication with the second channel 137.

A gasket 106 is disposed on the base plate 102 and is positioned betweenthe base plate 102 and the cover plate 104. The gasket can be formedfrom a flexible and corrosion resistant material, for example rubbers,polymers, plastics, silicone, etc. The gasket 106 includes an outer ring106 a and an inner divider 106 b. The outer ring of the gasket 106 ispositioned around the first cavity 111 and the second cavity 131, whilethe divider 106 b is positioned between the first cavity 111 and thesecond cavity 131. When the base plate 102 is coupled to the cover plate104, the gasket 106 forms a fluid tight seal between a top surface ofthe base plate 102 and a bottom surface of the cover plate 104 with theportions of the base plate 102 and the cover plate 104 in contact withthe gasket 106. In this manner, the gasket 106 fluidically isolates thetwo spaces formed between base plate 102 and the cover plate 104 thatare disposed between the outer ring 106 a and divider 106 b of thegasket 106, thereby dividing the valve 100 into the pressure portion 110and the suction portion 130. Thus, fluid communication between thesuction portion 130 and the pressure portion 110 can occur only via thefirst channel 122 and the second channel 137 by flowing through thechamber formed between the depression 108 of the cover plate 104 and themembrane 109, as described herein.

A pressure plate 112 is disposed on the base plate 102 in the pressureportion 110. The pressure plate 112 includes a first anchoring portion113, a first sealing portion 114 and a first biasing portion 115connecting the first anchoring portion 113 and the first sealing portion114. The pressure plate 112 can be formed from any suitable material,for example, metals (e.g., aluminum, stainless steel, alloys, etc.) andcan be formed using any suitable method, for example etching, stamping,forging, etc.

The first anchoring portion 113 is configured to anchor the pressureplate 112 to the base plate 102. As shown in FIG. 1, the first anchoringportion 113 can include a slot or other opening configured to engage afirst anchor 118 disposed on the base plate 102 (e.g., formed during themanufacturing the base plate 102) positioned in the pressure portion110, such that the first anchoring portion 113 is immovably coupled tothe first anchor 118. The cover plate 104 can include a matching cavityto receive at least a portion of the first anchor 118 such that firstanchoring portion 113 is trapped and thereby fixedly disposed betweenthe base plate 102 and the cover plate 104. In other embodiments, thefirst anchoring portion 113 can be fixedly coupled to the base plate 102using adhesives, rivets or removable coupled to the base plate 102 usingscrews, nuts, bolts or any other suitable fastener or couplingmechanism.

The pressure plate 112 can be formed with a large pretension in thebiasing portion 115. As shown in FIG. 1, the first biasing portion 115includes a pair of beams extending from the first anchoring portion 113to the first sealing portion 114. At least a portion of the firstbiasing portion 115 can be disposed within the first cavity 111. Thefirst biasing portion 115 can be configured to flex or otherwise bendabout the first anchoring portion 113 such that the first sealingportion 114 can be move proximal or distal relative to the base plate102 and the cover plate 104 within the first cavity 111. The pretensionin the first biasing portion 115 allows the first biasing portion 115 tooperate like a leaf spring and flex or elastically bend about the firstanchoring portion 113. This allows the first sealing member 114 to movebetween a first configuration and a second configuration, as describedherein. The first biasing portion 115 exerts a biasing force on thefirst sealing portion 114 in the first configuration and/or the secondconfiguration to urge the first sealing portion 114 to move proximaland/or distal relative to the base plate 102 and the cover plate 104.

In particular embodiments, the pretension in the first biasing portion115 is configured to urge the first sealing portion 114 towards thefirst channel 122. In other embodiments, a biasing member (not shown)can be coupled to the first biasing portion 115 or the first sealingportion 114 to bias the first sealing portion 114 towards the firstchannel 122. For example, any suitable biasing member (e.g., a springsuch as a helical spring, a Belleville spring, a leaf spring, etc.) canbe disposed on the base plate 102 beneath the first biasing portion 115or the first sealing portion 114 to bias the first sealing portion 114towards the first channel 122.

The first sealing portion 114 is disposed in the first cavity 111 andconfigured to move between the first configuration and the secondconfiguration within the first cavity 111. The first sealing portion 114is substantially flat and is configured to form a fluid tight seal withthe first channel 122. In some embodiments, a first sealing member 120can be positioned proximal to an outlet of the first channel 122. Thefirst sealing member 120 can, for example, include an O-ring. The firstsealing member 120 is configured to form a first fluid tight seal withthe first sealing portion 114 when the first sealing portion contactsthe first sealing member 120 in the second configuration, as describedherein.

The suction plate 132 is disposed in the suction portion 130. Thesuction plate 132 includes a second anchoring portion 133, a secondsealing portion 134 and a second biasing portion 135 connecting thesecond anchoring portion 133 to the second sealing portion 134. Thesuction plate 132 can have a structure which is substantially similar tothe pressure plate 112 and is therefore, not described in further detailherein.

As described with respect to pressure plate 112, the second biasingportion 135 included in the suction plate 132 also has a pretension. Inparticular embodiments, the pretension in the second biasing portion 135is configured to urge the second sealing portion 134 towards the inletpassageway 136. In other embodiments, a biasing member (not shown) canbe coupled to the second biasing portion 135 or the second sealingportion 134 to bias the second sealing portion 134 towards the inletpassageway 136. For example, any suitable biasing member (e.g., a springsuch as a helical spring, a Belleville spring, a leaf spring, etc.) candisposed between the bottom surface of the cover plate and the secondbiasing portion 135 or the second sealing portion 134 to bias the secondsealing portion 134 towards the inlet passageway 136.

As shown in FIG. 1, the second anchoring portion 133 can also include aslot or other opening configured to engage a second anchor 138 disposedon the base plate 102 in the suction portion 130 such that the secondanchoring portion 133 is immovably coupled to the first anchor 138. Asdescribed with respect to the pressure plate 112, the cover plate 104can also include a matching cavity to receive at least a portion of thesecond anchor 138 such that second anchoring portion 133 is trapped andthereby fixedly positioned between the base plate 102 and the coverplate 104. In other embodiments, the second anchoring portion 133 can befixedly coupled to the base plate 102 using adhesives, rivets orremovable coupled to the base plate 102 using screws, nuts or any othersuitable fastener or coupling mechanism.

The pretension in the second biasing portion 135 allows the secondbiasing portion 135 to flex or bend about the second anchoring portion133 to allow the second sealing portion 134 to move between the firstconfiguration and the second configuration, as described in greaterdetail below. The second biasing portion 115 exerts a biasing force onthe second sealing portion 134 in the first configuration and/or thesecond configuration to urge the second sealing portion 134 to moveproximal and/or distal relative to the base plate 102 and the coverplate 104, within the second cavity 131.

The second sealing portion 134 is disposed in the second cavity 131. Thesecond sealing portion 134 is substantially flat and is configured toform a fluid tight seal with the inlet passageway 136. In someembodiments, a second sealing member 140 can be positioned at an inletof the inlet passageway 136. The second sealing member 140 can include,for example an O-ring. The first sealing member 120 is configured toform a second fluid tight seal with the second sealing portion 134 whenthe second sealing portion 134 contacts the second sealing member 140 inthe second configuration, as described herein.

The valve 100 can be included in pump to pump a fluid, for example anexhaust reductant (e.g., a diesel exhaust reductant). FIG. 3 shows aside cross-section of the valve 100 coupled to a membrane 109 of a pump,with the pressure plate 112 and the suction plate 132 in the firstconfiguration and the second configuration. The membrane 109 is disposedon the top surface of the cover plate 104 distal to the base plate 102such that the chamber is formed between the depression 108 of the coverplate 104 and a surface of the membrane 109 proximal to the top surfaceof the cover plate 104.

The inlet passageway 136 is fluidically coupled via an inlet conduit 162to a reservoir or otherwise supply of fluid (e.g., an exhaust reductantstorage tank). The outlet passageway 116 is fluidically coupled to anoutlet conduit 164. The outlet conduit 164 can be in fluidiccommunication with a system (e.g., an SCR system). In one embodiment,the inlet conduit 162 and the outlet conduit 164 can include hoses orpipes. In another embodiment, the inlet conduit 162 and the outletconduit 164 can be defined in a plate which is coupled to a bottomsurface of the base plate 102 such that the inlet conduit 162 and theoutlet conduit 164 are in fluidic communication with the inletpassageway 136 and the outlet passageway 116, respectively.

As described before, the valve 100 is movable between a firstconfiguration and a second configuration. In the first configuration,the first sealing portion 114 of the pressure plate 112 is distal to thefirst channel 122 and the second sealing portion 134 of the suctionplate 132 is proximal to the inlet passageway 136. In the secondconfiguration, the first sealing portion 114 of the pressure plate 112is proximal to the first channel 122, and the second sealing portion 134of the suction plate 132 is distal to the inlet passageway 136.

Expanding further, in a first configuration the first sealing portion114 of the pressure plate 112 (shown by solid line in FIG. 3) is distalto the first channel 122, and the second sealing portion 134 of thesuction plate 132 (shown by solid line in FIG. 3) is proximal to theinlet passageway 136. For example, the pretension in the second biasingportion 135 can urge the second sealing portion 134 of the suction plate132 towards the inlet passageway 136. In particular embodiments, thepretension in the second biasing portion 135 can be sufficient to urgethe second sealing portion 134 towards the inlet passageway 136 suchthat the second sealing portion 134 forms the second fluid tight sealwith the second sealing member 140 in the first configuration. In thisway, the fluid is prevented from entering the second cavity 131 in thefirst configuration.

The first biasing portion 115 can be elastically bent or otherwisedeformed about the first anchoring portion 112 in the firstconfiguration to move the first sealing portion 114 distal from thefirst channel 122. In particular embodiments, the pretension in thefirst biasing portion 115 can be configured to urge the first sealingportion 114 towards the first channel 122 and thereby, form the firstfluid tight seal with the first sealing member 120 to fluidly seal thefirst channel 122. A positive pressure may be applied on the firstsealing portion 114 to move the first sealing portion 114 distal fromthe first channel 122, as described herein.

Furthermore, in the first configuration, at least a portion of themembrane 109 can be in contact with a top surface of the cover plate 104such that there is little or no distance between the membrane 109 andthe cover plate 104. Thus, the chamber which forms between the membrane109 and the depression 108 of the cover plate 104 is not present in thefirst configuration.

The pump can be actuated to displace at least the portion of themembrane 109 in contact with the depression 108 distal from thedepression 108, as shown by the arrow A. A space is thus producedbetween the membrane 109 and the depression 108 which defines thechamber. Furthermore, the displacement of the membrane 109 produces anegative pressure or suction in the first channel 122 and the secondchannel 137 of the cover plate 104.

The suction draws the first sealing portion 114 of the pressure plate112 and the second sealing portion 134 of the suction plate 132 towardsthe first channel 122 and the second channel 137. This moves the valve100 into the second configuration such that the first sealing portion114 is proximal to the first channel 122 and the second sealing portion134 is distal to the inlet passageway 136. The dotted lines in FIG. 3show the first sealing portion 114 and the second sealing portion 134 inthe second configuration. As described before, the movement of the firstsealing portion 114 and the second sealing portion 134 can result inflexing or otherwise elastic bending of the first biasing portion 115and the second biasing portion 135 about the first anchoring portion 113and the second anchoring portion 133, respectively.

In the second configuration, the first sealing portion 114 contacts thefirst sealing member 120 forming a first fluid tight seal with the firstsealing member 120, thereby fluidly sealing the first channel 122.Moreover, movement of the second sealing portion 134 distal from theinlet passageway 136 removes the second fluid tight seal such that thefluid can be drawn via the inlet conduit 162 and through the inletpassageway 136 into the second cavity 131, as shown by the arrow B.

The negative pressure further draws the fluid through the second channel137 into the chamber. As the fluid flows under the membrane 109 in thechamber, the negative pressure inside the chamber reduces and iseventually removed. This also removes the negative pressure in thesecond channel 137 and thereby the suction on the second sealing portion134. Removal of the negative pressure allows the flexed or elasticallybent second biasing portion 135 to bend towards the inlet passageway136. The second sealing portion 134 also moves towards the inletpassageway 136 and into the first configuration forming the second fluidtight seal with the second sealing member 140 thereby fluidly sealingthe inlet passageway 136.

In some embodiments, the removal of the negative pressure can also urgethe first biasing member to bend about the first anchoring portion 113such that the first sealing portion 114 moves distal from the firstchannel 122. In other embodiments, in which the pretension in the firstbiasing portion 115 is configured to urge the first sealing portion 114towards the first channel 122, the membrane 109 can also be movedproximal to the cover plate 104 to exert a positive pressure on thefirst channel 122. The positive pressure acts on the first sealingportion 114 to urge the pressure plate 112 into the first configuration.

Expanding further, movement of the membrane 109 towards the cover plate104 minimizes the space between the membrane 109 and the cover plate104. A positive pressure is created in the first channel 122 whichovercomes the tension of the first biasing portion 115. The firstbiasing portion 115 flexes or elastically bends removing the first fluidtight seal. This allows the fluid to flow into the first cavity 111 andaround the first sealing portion 114 into the outlet conduit 164 via theoutlet passageway 116, as shown by the arrow C.

FIG. 4 shows a perspective view of a valve 200 according to anotherembodiment. As with the valve in FIG. 1, the valve 200 can be includedin a pump, for example a pump configured to deliver an exhaust reductantto an SCR system. The valve 200 includes a base plate 202, a cover plate204, a pressure portion 210 that includes a pressure plate 212, and asuction portion 230 that includes a suction plate 232. FIG. 5A shows aside cross-section view of the pressure portion 210, and FIG. 5B shows aside cross-section of the suction portion 230 of the valve 200.

The base plate 202 defines an inlet passageway 236 and an outletpassageway 216 therethrough (FIGS. 2A and 2B). The base plate 202 issubstantially similar to the base plate 102 with one notable exception.The inlet passageway 236 is defined by a second port 240 disposedthrough the base plate 202. The second port 240 can be formed from asoft but rigid material which can withstand corrosion from a harsh fluid(e.g., an exhaust reductant such as an aqueous urea solution). Suitablematerials can include, for example rubber or polymers. The second port240 is inserted through base plate (e.g., through a passageway definedin the base plate 202) to defined the inlet passageway 236. A portion ofthe second port 240 proximal to the cover plate 204 is configured toform a second fluid tight seal with a second sealing portion 234 of thesecond suction plate 232 such that an external sealing member (e.g., thesecond sealing member 140 included in the valve 100) is not required.

A first cavity 211 is also defined in the base plate 202 in the pressureportion 210. The first cavity 211 is configured to receive at least aportion of the pressure plate 212, as described herein, and is influidic communication with the outlet passageway 216.

The cover plate 204 is disposed on the base plate 202. The cover plate204 defines a first channel 222 in the pressure portion 210 and a secondchannel 237 in the suction portion 230. At least a portion of the coverplate 204 between the first channel 222 and the second channel 237 candefine a depression 208. The cover plate 204 is substantially similar tothe cover plate 104 described with respect to the valve 100 with oneexception. The first channel 222 is defined by a first port 220 disposedthrough the cover plate 204. The first port 220 can be formed from thesame materials as the second port 240 and can withstand corrosion fromthe fluid (e.g., an exhaust reductant). The first port 220 is insertedthrough the cover plate 204 (e.g., through a passageway defined in thecover plate 204) and defines the first channel 222 therethrough.Furthermore, a portion of the first port 220 proximal to the base plate202 is structured so as to form a first fluid tight seal with a firstsealing portion 214 of the pressure plate such that an external sealingmember (e.g., the first sealing member 120) is not required.

The second channel 237 is aligned with the outlet passageway 216 and isconfigured to allow fluid drawn into the chamber to be communicated backinto the cover plate 204 and into the outlet passageway 216. The coverplate 204 also defines a second cavity 231 in the suction portion 230.The second cavity 231 is configured to receive at least a portion of thesuction plate 232.

A gasket 206 is disposed on the base plate 202 and is positioned betweenthe base plate 202 and the cover plate 204. The gasket 206 can be formedfrom a flexible and corrosion resistant material, for example rubbers.The gasket 206 includes an outer ring 206 a and an inner divider 206 bconfigured to divide the valve into the pressure portion 210 and thesuction portion 230 which are fluidically isolated from each otherthrough the valve 200, as described with respect to the valve 100.

A pressure plate 212 is disposed on the base plate 202 in the pressureportion 210. The pressure plate 212 includes a first anchoring portion213, a first sealing portion 214 and a first biasing portion 215connecting the first anchoring portion 213 and the first sealing portion214. The first anchoring portion 213 can include a slot configured toengage a first anchor 218 disposed on the base plate 202 positioned inthe pressure portion 210, such that the first anchoring portion 213 isimmovably coupled to the first anchor 218. The pressure plate 212 can besubstantially similar to the pressure plate 110 described with respectto the valve 100, and therefore, not described in further detail herein.

The suction plate 232 is disposed in the suction portion 230. Thesuction plate 232 includes a second anchoring portion 233, a secondsealing portion 234 and a second biasing portion 235 connecting thesecond anchoring portion 232 to the second sealing portion 234. Thesecond anchoring portion 233 can also include a slot configured toengage a second anchor 238 disposed on the base plate 202 in the suctionportion 230 such that the second anchoring portion 233 is immovablycoupled to the first anchor 138. The suction plate 232 is substantiallysimilar to the suction plate 132 described with respect to the valve100, and therefore not described in further detail herein

The valve 100, 200 or any of the other valves described herein can beused in a wide variety of pumps, for pumping any fluid (e.g., water,diesel exhaust fluid, oil, solvents, etc.). For example, the valves 100,200 or any other valve described herein can be included in a pumpconfigured to pump an exhaust reductant from a storage tank to a SCRsystem included in an aftertreatment system. FIG. 6 shows a schematicflow diagram of an exemplary aftertreatment system 300. Theaftertreatment system 300 includes a storage tank 360 for storing liquidexhaust reductant, a pump 370 that includes the valve 100, and an SCRsystem 350. The aftertreatment system 300 can be used to a treat anexhaust gas (e.g., a diesel exhaust gas) produced by an engine (e.g., adiesel engine) to remove any NOx gases included in the exhaust gas.

The storage tank 360 is configured to store an exhaust reductant. Insome embodiments, in which the exhaust gas is a diesel exhaust gas, theexhaust reductant can include a diesel exhaust reductant. Such exhaustreductants can include, for example urea or an aqueous solution of urea(e.g., the exhaust reductant available under the tradename ADBLUE®).

The SCR system 350 is fluidly coupled to the engine and configured toreceive an exhaust gas (e.g., a diesel exhaust gas) from the engine. TheSCR system 350 includes one or more catalysts formulated to reduce theexhaust gas in the presence of the exhaust reductant and remove any NOxgases from the exhaust gas.

The pump 370 is positioned downstream of the storage tank 360 andupstream of the SCR system 250. While shown as including the valve 100,in other embodiments, the pump 370 can include the valve 200 or anyother valve described herein. The pump 370 is fluidly coupled to thestorage tank 360 and the SCR system 350. The pump 370 is configured topump the exhaust reductant from the storage tank 360 to the SCR system350 via the valve 100, as described before herein. For example, the pump370 can be fluidly coupled to a fluid injector disposed on the SCRsystem 350 and configured to communicate the exhaust reductant into theSCR system 350.

FIGS. 7A and 7B show optical images of a bottom surface of a cover plateand a top surface of a base plate of a valve, respectively. The valve issubstantially similar to the valve 100 described herein. FIG. 7B shows apressure plate and a suction plate disposed on the base plate andanchored at a first anchor and a second anchor respectively. FIG. 7Ashows a second cavity, a first channel and a second channel defined inthe cover plate, and a first sealing member disposed at an outlet of thefirst channel.

In one previous test of a valve constructed according to one exemplaryembodiment, the valve was subjected to about 400 hours of operation and9 freezing cycles. Slight corrosion of the tension arms of each of thepressure plate and the suction plate was observed after initial use, butno increase in corrosion was observed after 400 hours of use. Even afternine (9) freezing cycles, no visible damage to the valve was observed.

FIG. 8A is a plot of pressure profile of a pump which includes the valveof FIGS. 7A and 7B for operation at nominal system pressure. The y-axisscale denotes the pressure and flow as a percentage of a specified ordesired value of a pressure and flow desired from the pump at apredetermined operating condition of the pump. The pump equipped withthe valve of FIGS. 7A-B is able to build and maintain outlet sidepressure at 100% of the specified (also referred to as “adjusted”)value. The flow however, exceeds the specified or expected value of theflow at the specified pressure by 40%, indicating that the pumpincluding the valve of FIGS. 7A-B is able to accommodate higher flow atthe specified pressure. Thus, a lower pressure can be used to achieve adesired flow which can lower energy requirements and reduce costs.

FIG. 8B is a plot of suction developed in a pump that includes thevalve, demonstrating self priming ability which can be achieved with thevalve. The y-axis denotes the level of the vacuum as a percentage of aspecified value of the vacuum at a predetermined operating condition ofthe pump. The pump equipped with the valve is able to create a vacuumpressure in a suction line fluidly coupled to the pump thereby allowingself priming up to a certain head height. As seen in FIG. 8B, at arequested or otherwise desired negative pressure of 0 bar, the actualnegative pressure achieved by the pump including the valve is about 2.5×(about 250%) lower than the requested pressure. This demonstrates, thatvalve is capable of providing sufficient vacuum to draw a fluid (e.g.,water or exhaust reductant) from a reservoir at a specified negativepressure.

As used herein, the singular forms “a”, “an” and “the” include pluralreferents unless the context clearly dictates otherwise. Thus, forexample, the term “a member” is intended to mean a single member or acombination of members, “a material” is intended to mean one or morematerials, or a combination thereof.

As used herein, the terms “about” and “approximately” generally meanplus or minus 10% of the stated value. For example, about 0.5 wouldinclude 0.45 and 0.55, about 10 would include 9 to 11, about 1000 wouldinclude 900 to 1100.

The terms “coupled,” “connected,” and the like as used herein mean thejoining of two members directly or indirectly to one another. Suchjoining may be stationary (e.g., permanent) or moveable (e.g., removableor releasable). Such joining may be achieved with the two members or thetwo members and any additional intermediate members being integrallyformed as a single unitary body with one another or with the two membersor the two members and any additional intermediate members beingattached to one another.

It is important to note that the construction and arrangement of thevarious exemplary embodiments are illustrative only. Although only a fewembodiments have been described in detail in this disclosure, thoseskilled in the art who review this disclosure will readily appreciatethat many modifications are possible (e.g., variations in sizes,dimensions, structures, shapes and proportions of the various elements,values of parameters, mounting arrangements, use of materials, colors,orientations, etc.) without materially departing from the novelteachings and advantages of the subject matter described herein. Othersubstitutions, modifications, changes and omissions may also be made inthe design, operating conditions and arrangement of the variousexemplary embodiments without departing from the scope of the presentinvention.

What is claimed is:
 1. A valve, comprising; a base plate defining aninlet passageway and an outlet passageway, the inlet passageway includedin a suction portion of the valve and the outlet passageway included ina pressure portion of the valve; a cover plate disposed on the baseplate, the cover plate defining a first channel in the pressure portionand a second channel in the suction portion; a pressure plate disposedon the base plate in the pressure portion, the pressure plate includinga first anchoring portion, a first sealing portion, and a first biasingportion connecting the first anchoring portion and the first sealingportion; a suction plate disposed on the base plate in the suctionportion, the suction plate including a second anchoring portion, asecond sealing portion, and a second biasing portion connecting thesecond anchoring portion to the second sealing portion; a first sealingmember positioned proximal to an outlet of the first channel; and asecond sealing member positioned at an inlet of the inlet passagewaywithin the base plate, wherein the valve is movable between: a firstconfiguration, in which the first sealing portion of the pressure plateis distal to the first channel and the second sealing portion of thesuction plate is proximal to the inlet passageway, and a secondconfiguration, in which the first sealing portion of the pressure plateis proximal to the first channel, and the second sealing portion of thesuction plate is distal to the inlet passageway, wherein the firstsealing member is configured to form a first fluid tight seal with thefirst sealing portion in the second configuration, and wherein thesecond sealing member is configured to form a second fluid tight sealwith the second sealing portion in the first configuration.
 2. The valveof claim 1, wherein the movement of the first sealing portion and thesecond sealing portion between the first configuration and the secondconfiguration results in a flexing of the first biasing portion aboutthe first anchoring portion, and a flexing of the second biasing portionabout the second anchoring portion, respectively.
 3. The valve of claim1, wherein the valve is movable into the second configuration byapplying a negative pressure in the first channel and the secondchannel, the negative pressure moving the first sealing portion proximalto the first channel and fluidly sealing the first channel, the negativepressure also moving the second sealing portion distal from the inletpassageway, the movement of the second sealing portion allowing a fluidto be drawn into the suction portion via the inlet passageway.
 4. Thevalve of claim 3, wherein the valve is movable into the firstconfiguration by removing the negative pressure, the removing allowingthe first biasing portion to flex away from the first channel and movethe first sealing portion distal from the first channel, the removingfurther allowing the second biasing portion to flex towards the inletpassageway and seal the inlet passageway, the movement of the firstsealing portion allowing at least a portion of the fluid to becommunicated through the first channel and about the first sealingportion into the outlet passageway.
 5. The valve of claim 1, wherein atleast a portion of the cover plate between the first channel and thesecond channel defines a depression, the depression cooperating with amembrane disposed on the cover plate to form a chamber, the chamberallowing fluidic communication between the first channel and the secondchannel.
 6. The valve of claim 1, wherein a first cavity is defined inthe base plate, and wherein the first sealing portion is movable betweenthe first configuration and the second configuration within the firstcavity.
 7. The valve of claim 6, wherein a second cavity is defined inthe cover plate, and wherein the second sealing portion is movablebetween the first configuration and the second configuration within thesecond cavity.
 8. The valve of claim 1, further comprising: a firstanchor disposed on the base plate in the pressure portion, the firstanchoring portion of the pressure plate immovably coupled to the firstanchor; and a second anchor disposed on the base plate in the suctionportion, the second anchoring portion of the suction plate immovablycoupled to the second anchor.
 9. The valve of claim 1, furthercomprising: a gasket disposed on the base plate, the gasket positionedso as to divide the valve into the pressure portion and the suctionportion.
 10. The valve of claim 1, further comprising a first portdisposed through the cover plate in the pressure portion, the first portdefining the first channel therethrough, a portion of the first portproximal to the base plate configured to form a first fluid tight sealwith the first sealing portion in the second configuration.
 11. Thevalve of claim 10, further comprising a second port disposed through thebase plate in the suction portion, the second port defining the inletpassageway, a portion of the second port proximal to the cover plateconfigured to form a second fluid tight seal with the second sealingportion in the first configuration.